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.Figure 10.22The cavity has been filled with ProRoot MTA andthe surface wiped free of excess material with a dampsponge.Figure 10.21A view at high power showing the compacted guttaFigure 10.23percha following root end cavity preparation.A previous attempt at root end surgery using amalgamas a root end filling can be seen in this maxillaryhealing following its use as a root-end fillingcentral incisor (blue arrow).The case was retreated non-material has generally been shown to be goodsurgically to ensure that the root canal was adequately(Figures 10.26 10.41).30 disinfected and the gutta percha root filling can be seenat the canal orifice (red arrow).The amalgam retrogradefilling had been placed incorrectly and the root canalhad not been prepared during surgery.It is perhaps notSuper EBAsurprising that the previous attempt at endodontic sur-Super EBA (ethoxybenzoic acid) is a modifiedgery failed.The value of using an operating microscopezinc oxide eugenol cement that has been is clearly highlighted. SURGICAL PROCEDURES 187Figure 10.24The amalgam filling was removed with ultrasonics andthe root tip minimally resected to remove the bevel thathad been made during previous surgery.An ultrasonic tipwas used to prepare a root end cavity, and compacted Figure 10.26gutta percha can be seen at the base of it.A view at high magnification following root end prepara-tion with ultrasonics.The gutta percha is compacted witha microplugger as it becomes thermoplasticized by theultrasonic tip.Figure 10.25The case was filled with MTA.Because of the shortenedroot length it was not possible to remove all the staineddentine from the root tip without compromising the tooth.However, the root canal has been prepared and filled to adepth of 3 4 mm and should be well sealed.Figure 10.27The root end cavity has been filled with IRM, which isburnished.shown to have better sealing properties thanamalgam and osseous repair following Microleakage was observed in root end cavitiessurgery.31 The material is susceptible to mois- that were prepared ultrasonically and filledture in the operative field and this may have with Super EBA.18 It has been recommended asa negative effect on the quality of seal.26 a root end filling (Figures 10.42 10.44). 188 ADVANCED ENDODONTICS: CLINICAL RETREATMENT AND SURGERYFigure 10.30The case filled with IRM and the root surface polished.Figure 10.28When the IRM has set, the resected root and filling materialcan be polished with an ultrafine diamond or tungstencarbide bur.Figure 10.31Non-surgical retreatment was completed on thismandibular molar.Unfortunately, there was a persistentbuccal sinus tract which did not heal.Root end surgerywas recommended.Figure 10.29material has been observed.32 Glass ionomerThe completed root end preparation in a maxillarycan be placed across the entire resected rootpremolar.end, which is saucerized.This should alsoeffectively seal exposed dentinal tubules.Glass Ionomer There are numerous clinical reports thatsupport the use of glass ionomer.33There is a dynamic physicochemical bondbetween dentine and glass ionomer cementwhich enables the material to provide a sealComposite Resinwhen used as a root end filling.This sealingability has been shown to be better than amal- Dentine-bonded composite resin has beengam, and osseous healing adjacent to the utilized as a root-end filling material, and in SURGICAL PROCEDURES 189Figure 10.34Figure 10.32The completed root end filling in the mesial root, showingA triangular flap was raised to provide good surgicalan isthmus connecting the two canals.This would notaccess.have been visible without an operating microscope.Figure 10.35Figure 10.33A view of the distal canal, showing the completed rootThe lesion was curetted and the bony crypt enlarged to end filling.allow root resection and root end preparation of bothroots.Conditioning of the Resected Root Endthe hands of skilled operators has shown Some operators have recommended using anpromising results.Reformation of the acidic conditioner on the resected root end toperiodontal apparatus and cementum has expose collagen fibrils and encourage healing.been reported adjacent to composite resin.This method has been used following perio-The operating site must be moisture-free, dontal surgery to condition the root surfacewhich can be technically challenging.and stimulate reformation of the periodontalTherefore, placement of the material over the ligament.35 In dogs, demineralization of theentire resected root end has been advocated.root end using citric acid has been shown toThe material has superior sealing ability to result in the predictable formation of newamalgam.34 cementum
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